SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '44247f86f348b633c02f024b6d212bdc61654033f66cb8818db59935a5260641' 
  AND token = 'PyZrnqcvESXjh1Vyjk91JRdVUJPpjustKhX81Q/WLoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}